The present invention relates to a semiconductor device and a manufacturing method thereof, and more particularly, a semiconductor device with a silicide region, and a manufacturing method thereof.
Some semiconductor devices include a silicide layer and a plug. For example, Japanese Unexamined Patent Publication No. 2008-205010 (Patent Document 1) discloses a manufacturing method of such a semiconductor device including the following steps.
A silicide layer which is a nickel silicide layer or a nickel-platinum silicide layer is formed over a semiconductor substrate. Holes are formed in the silicide layer covered with an insulating film over the semiconductor substrate by dry etching. A Ti layer is formed at an inner surface of each hole by a chemical vapor deposition (CVD) method. A Ta layer is formed as a barrier metal layer on the Ti layer in the hole by sputtering. A copper layer is formed on the barrier layer to fill the hole, and the CMP is carried out thereby to form a copper plug.
As disclosed in the above patent document, a TiN layer may be formed between the barrier metal layer and the Ti layer by sputtering. The barrier metal layer is not limited to the Ta layer, and may be comprised of any one of or a combination of a Ta layer, TiN, TaN, Ru, WN, W—N—C, Ti—Si—Nx, Ta—Si—Nx, and W—Si—Nx.